The present invention is directed to a universal seed metering disc. In particular, it relates to a seed metering disc with a seed retention plate defining a seed cell. It finds particular application in use with varying sizes of seeds.
In many agricultural areas, large planters equipped with numerous row units are used to plant crop fields. The row units follow the planter and discharge seeds into the soil at a selected rate. In order to create uniformity and proper crop distance, seed meters are attached to the row units. Large seed reservoirs store the seeds as the planters move across the crop fields. Seeds are released from the seed reservoirs and are evenly dispersed between the row units. The seeds travel down the row unit and are discharged onto a rotating seed disc wherein the seeds gravitate into a series of specially-molded seed pockets, spaced to provide adequate crop distance. The seeds are retained in the seed pockets and then individually enter seed cells located at the periphery of the seed discs. The seed cells are typically sized to retain a single seed of a particular size and deliver it to the soil at a fixed point in the rotation of the seed disc. See, e.g., U.S. Pat. No. 5,058,766 assigned to Kinze Mfg. Due to the design of the seed cells, seed metering discs will only distribute seeds properly if the seeds are of the size the seed discs are designed to handle. Therefore, when planting more than one type of crop, and thus using different seed sizes, more than one set of seed metering discs must be purchased and installed to allow for proper seed metering. While the large size seed metering discs can be used for smaller seeds, the design of the seed cells for large discs does not allow for proper delivery of small seeds to the soil. Instead of falling at the designated seed delivery point, the smaller seeds slip from the seed cells at various points during seed disc rotation and are thus delivered in a non-uniform pattern. Typically, the smaller seeds fall out the backside of the seed cell and therefore fall to the soil outside the designated crop row.